Free Network and DNS Tools

Quick, single checks for when you do not need a full subdomain scan. Each one answers one question about an IP, hostname or URL.

Reverse IP Lookup
Find every domain and hostname hosted on an IP address, or on the server behind a hostname.
DNS Checker
Look up A, AAAA, MX, NS, TXT, CNAME, SOA and CAA records and compare answers from major public resolvers.
Subdomain IP History
See every IP address a domain or subdomain has pointed to over time, with when each was last seen.
IP Reputation Checker
Check whether an IP address has been reported for abuse, spam, scanning or malware, and who operates it.
URL Reputation Checker
Check a website or URL against phishing, malware and spam blocklists before you open it.
HTTP Headers Checker
Fetch the HTTP response headers of any site and see which security headers it is missing.
Subdomain Finder
The full scan: every known subdomain of a domain with IPs, hosting, open ports and CVEs.